Lock for meter-box covers



Nov. 10, 1925. 1,561,449

0. J. ARMSTRONG LOOK FOR METER BOX COVERS Filed May 19, 1925 "E llllillliliiifi q II I 'I'IIIIII) Charles lflrmslv'o lo@r%ui f Qtboc we 1 Patented Nov. 10, 1925.

UNITED STATES CHARLES JOHN ARMSTRONG, OF AUSTIN, TEXAS.

LOCK FOR METER-BOX COVERS.

Application filed May 19, 1925. Serial No. 31,348.

which is carried by the bottom of the cover and is adapted to engage a portion of the cover supporting flange of the top plate of a meter box cover so as to hold the cover securely in position until the lock is actuated by means of a key provided for that purpose.

A further object is to provide a lock which can be operated readily and the parts of which can be assembled easily but will not become accidentally displaced.

With the foregoing and other objects in view which will appear as the description proceeds the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the in vention herein disclosed may be made within the scope of what is claimed without departing from the spirit of the invention.

In the accompanying drawings the preferred form of the invention has been shown.

In said drawings,

Figure 1 is a vertical transverse section through a metal box cover and adjacent parts, the lock being shown in elevation.

Figure 2 is a bottom plan view of the structure shown in Figure 1.

Figure 3 is a section on line 33 Figure 1, the bolt stem and spring being shown in plan, the bolt being shown retracted.

Figure 4: is a vertical longitudinal section through the lock showing the key in engagement therewith and the bolt in normal position.

Figure 5 is a bottom plan view of a portion of the cover showing the centering boss of the tumbler.

Referring to the figures by characters of reference 1 designates the top plate or ring of a meter box provided with an opening 2 around which extends a flange 3. This opening is adapted to receive a cover plate & designed to rest on the flange 3.

Formed on the bottom or inner face of the cover is a lug 5 so shaped that, when the cover 1s in position, said lug will extend under the flange 3 as shown particularly in fig ures 1 and 2. Depending from the cover 1 at a point diametrically opposite the lug 5' is a guide lug 6 having an opening 7 therein. Another guide lug 8 extends downwardly from the cover 4 at a point between the lugs 5 and 6 and has an opening 9.

Cover 4 is formed with a keyhole 10 at a point between the lugs 6 and 8 and formed on the bottom face of the cover so as to extend partly around the keyhole is a circular boss 11 constituting a bearing or centering device for a tiunbler 12 which is recessed as at 13 to receive the boss.

Tumbler 12 is provided with a wing 14 and a key receiving slot 15 extends through the tumbler and is adaptedv to register with the keyhole 10 when the tumbler is in its normal position. This tumbler has a notch 16 in its periphery so located that, when the tumbler is in its normal position said notch will receive a lug 17 extending from the wall of an elongated housing 18. This housing extends under the tumbler 12 and constitutes a thrust bearing therefor and also serves to conceal the tumbler so that access thereto can only be had through the keyhole 10. The housing has an extension 19 into which the wing 1 1 normally projects as shown by dotted lines in Figure 2. A stem 20 projects from the housing and is slidable within the opening 9 while a bolt head 21 projects from the other end of the housing and is slidable within the opening 7. A spring 23 is mounted on stem 20 and bears at one end against housing 18 and at its other end against the lug. Thus this spring serves to hold the head 22 normally projected beyond lug 6 so that it can extend under the flange 3 at a point diametrically opposite the lug 5 and hold the cover 1 to its seat.

When it is desired to unlock the cover 1 it is necessary to use a key K of proper size and shape which is inserted through the keyhole 10 into the slot 15. Insertion of the key is limited by the bottom of the housing 18. The key is then turned in the proper direction so as to cause wing 14; to exert a wiping or cam-1ike action upon one wall of the housing extension 19. Thus the housing will be thrust backwardly relative to the key and spring 23 will be placed under increased compression, Consequently the housing and tumbler head 22 will be withdrawn from under flange 3 and with the parts thus located the cover can be lifted from its seat, key K being used as a handle for this purpose. After the cover has been'replaced on its seat the key can be rotated so as to bring it into position to be withdrawn through the keyhole 10. This will causethe wing 14 to swing back to normal position and spring 28 will therefore be allowed to return the bolt head and other parts to their normal positions. lVhile the parts are thus located the lug 17 projects into the V-shaped notch 16 and serves to hold the tumbler against rotation out of proper position relative to the keyhole.

What is claimed is:

1. The combination with a cover having a keyhole therein and guide lugs extending from the cover, of a housing slidable upon one face of the cover and having a lateral extension, a bolt head and a stem projecting in opposite directions respectively from the housing and slidable within the respective guide lugs, a tumbler mounted for rotation within the housing and having a Wing normally extending into the housing extension, there being a key receiving slot within the tumbler a spring for holding the housing and tumbler yieldingly in their normal positions and cooperating means on the for holding said tumbler against free rotation within the housing.

2. The combination with a cover having a keyhole and a centering boss adjacent the keyhole, of a tumbler mounted for rotation 011 the boss and having a key receiving slot normally registering with the keyhole, a spring pressed bolt connected to the cover, said bolt including a housing in which the tumbler is concealed, said housing having an extension, there being a wing upon the tumbler for wiping engagement with one wall of the extension, and cooperating means upon the housing and tumbler for holding said tumbler against free rotation within the housing.

3. The combination with a cover having a keyhole and a boss adjacent the keyhole, of a tumbler mounted for rotation on the boss and having a key receiving slot, there being a wing upon the tumbler, a bolt slidablc relative to the cover and connected thereto, said bolt having a housing movable relative to and concealing the tumbler, there being an extension on the housing one wall of which is adapted to be slidably engaged by the wing of the tumbler, cooperating means upon the tumbler and the housing for holding said tumbler against free rotation, and yielding means for maintaining the tumbler and the housing in normal positions.

4;. The combination with a cover having a keyhole, of a tumbler mounted for rotation, means for holding the tumbler against sliding movement relative to the cover, said tumbler having a key receiving slot normally registering with the keyhole, a bolt slidable relative to thecover and including a housing for the tumbler, cooperating means upon the tumbler and housing for sliding the boltwhen the tumbler is rotated, cooperating means upon the tumbler and housing for holding the tumbler against free rotation, and yielding means for holding the bolt and tumbler yieldingly in normal positions.

In testimony that I claim the foregoing as my own, I have hereto afiixed my signature.

CHARLES JOHN ARMSTRONG. 

